Thermal sealing machine



ISSheets-Sheet 1 H. F. WATERS THERMAL SEALING MACHINE Filed July20,`I940 INVENTOR Y F.' WH TERS FITTORNEY HHRR "Aug,` 12, 1941. H. F.WATERS 'THERMAL SEALING MACHINE Filed `July 20, 1940 Sheets-Sheet 2ATTORNEY Abars V2li, 2|, the work-support plates II3, ||4

'to be formed into a bag, for the sealing bars 26, 2| to contact withthe marginal portions F, G, ai'.l which the seams are to be formed. Ifadditional support is Arequired between the sealing are moved outwardlyon the supporting bars Ill,

'|||, rst loosening and then tightening the bolts H8, H9. The under partof a folded carton...

b1ank Bmay extend laterally beyond the marginal portions F and G of thefolded bag-forming bag A, in which circumstance the guide rails |2|,|22, are moved apart so that they will act on the side edges of thecarton-blank with the marginal portions F andG of the bag-forming blankinl proper position to be seamed by the sealing bars 20, 2|. Theadjustment lof the guide rails |2|, |22 is eiected through the screws|21, |28, Y'

and the slots |25, |26 in the guide rails.

. Withl the folded bag-forming sheet A, or with the assemblvof such asheet witha folded earton-formng sheet B, in position on theworksupport, and with the v'ends of the sealing bars 2 l,

22, extending over the fold C of the folded bagforming sheet A, the foottreadle 'I3 is pushedaway from the operator, swinging the arm I2 oi thebell-crank lever down, and carrying with it the equalizing bar V15, Theequalizing bar at its ends, pulls down the oppositely pivoted levers 80,8|, and these pull on the pull-rods 66, 61, which are attached to thelevers 6U, 6|, which levers carry the pins 63,64 which bear von thelevers 53, 54 and move the latch-contacting portions 56, 51 thereof outof contact with said latches. This allows the latches 5|, 52, to engagethe shafts 43, 44, and thereby clutch the cams 46, 41, to said shafts43, 44, which are driven by the motors 30, 3|.k The cams 46, 41, actingon the arms 48, 49, of the rock-shafts 36, v39, turn the saidrock-shafts 36, 39, and move the heads 33, 34 (carried by the arms 36,31, attached to said rock-shafts) toward the folded bag-iormingsheetlyingl on Vthe work-support with its marginal portions extendingover the backing members 23, 24. VThe heads 33, 34, to which theysealing bars 20, 2| are connected by a floating connection, pressthe-sealing bars against 'the marginal portions F and G ofthebag-forming sheet A. The downward movement 'of the heads 33, 34continues slightly beyond the point where the sealing bars make contactwith the bagforming sheet, so as to additionally tension the 4resilientmeans comprising the compression springs 95, 96. 'I'he cams 46, 41 byreason of their contour, maintain the heads 33, 34, at their lowermostposition through a certain interval of time. During this bag-formingsheet are .under the pressure of the treadle 13.

By the operation of the machine, as described, a. specially foldedbag-forming sheet, or such a sheet in a special assembly with a foldedcartonforming sheet as illustrated in Fig. 6, is simultaneously seamedat its two marginal portions F and G, and a bag which is seamed at itstwo sides by the seams K and L, closed at its bottom by the fold C, andopen at the top, is formed at one operation of the machine.

The invention may receive other embodiments than that herein specincallyillustrated and described.

'wnatiac1aimedis: g 1'. In a heat sealing mechine, the combination whichcomprises a pair of sealing units, each of said units including Vasealing bar and heating l v means and a backing member-for said bar,means for individually and independently displacing said units with thesealing bars in parallel spaced position with respect to each other toadjust the distance between the sealing bars of'said 1mits,.and meansfor simultaneously actuating said units to apply heat and pressure totwoparallel marginal strips of a sheet bearing fusible 5' material inone operation. 2. In a heat sealing machine. the combination 'whichcomprises a pair of sealing units: each of said units including asealing bar, heating means for said bar, a backing member for said bar,and

. an actuating mechanism for said bar to move the bar from aninoperative into an operative and heat sealing position;

means for independently displacing said units to adjust the distancebetween their respective sealing bars, means for units;

fixing said units in such adjusted position; and means in common forboth of said units for simultaneously initiating theoperation of bothunits. 3. In a. heat sealing machine', the combination which comprises apair of displaceable sealing heating means and a backing member forAsaid bar, an actuating mechanism for said bar adapted time the marginsofthe Vsprings 96, 96, etc.- and are also subject to the heat of thesealing bar. While thus under pressure and heat, the thermoplastic,materialof which the bag-forming sheet is made, or lined, or striped atthe place of seal, softens and welds to form the seam. By reason ofthefloating connection between the sealing bars 2U, 2i, and their heads,the work-contacting faces 85 o f the Seal' v ing bars can adjust oraccommodate themselves to the flat surface of the material, and therebyform a weld or joint of equal strength and se' curity the fun width .ofthe 'aforesaid workcontacting faces 85 of the sealing bars.

When the arms 48, 49, respectively of the .a

rock-shafts 38, 39, to which the 'heads 33,' 34 are connected, rideloil'of the high part ofthe sealing cams, springs |30. |3| move orreciprocate th e 15 common for both imita bai-,the

Vnislmlneansfor when actuated to apply the sealing bar against. v

each Aoi? said units including a sealing bar.-

a sheet interposed between the bar and the back ing member, drivingmeans for said'actuatlng mechanism, and means intermediate tosaid'drivingmeansandsaidactuatingmechanismto.

themv normally disconnected; and meansincommonforbothofsaiduniisoperableindependentlyfrom therelative positions ofthe units to simultaneouslyconnect the driving means o Veach unit to its corresponding actuatingmechanism.`

4. In a heat sealing machine. the combination which comprises a pair ofsealing units; each of said units including a heated sealing bar,abackingmemberadapstiddtowtgperatewithsaid sealingbarsof unibeingan'anged inparallel-spaced position, an actuating mechanism forsaid bar, drivingmeans for saidactuatins mechanism, anda said drivingmeans and said actimting mechaindivlduallyand displacingsaid unitstotheir respective clutch intermediate to independentlyvdiustthespacebetweeni.

bars: and means in tocame ahnultanemis operation oi.' the clutch in eachunit whereby said sealingbarswillbemoved'againstthe .correspondingbacking members to form parallel seams upon a fusible sheet interposedbetween the bars and the backing members.

5. A thermal sealing machine comprisinga pair oi sealing units, a commonbed for said units, alined ways on said bed on which saidl sealing unitsare seated in opposite relationship,

and on' whichV ways said units may be movedA toward and from one anotherto vary the space Y between the units, each of said units comprisingasealingbar,ameansforheatingthesame, and a platen or backing member, thesealing barandbackingmemberononeunitbeingarranged parallel to those onthe other unit, and means i'or simultaneously actuating said sealingbars to press and heat marginal portions of a folded sheet between thesealing bars and the backing members, to form parallel seams at oppositesides of a sheet.

6. A thermal sealing machine comprising a pair of sealing umts. a commonbed i'or said units,

alined ways on said bed on which said sealing units are sealed inopposite relationship, and on which ways said lunits may be moved towardand from one another to vary the space between the units, each of saidumts comprising a sealing bar.' a means for heating the same, a platenor backing member, means for reciprocating Vthe sealing bar, a motor fordriving said reciprocating means and a clutch between said rmotor andsaid reciprocating means, the sealing bar and backing member oi one unitbeing arranged parallel to those on the other unit, and means Vforsimultaneously operating said clutches to connect said sealing barreciprocatlngmeans to said motors, to ultaneously actuateV said sealingbars, to press d heat the marginal portions of a folded sheet betweenthe sealing bars and the backing members to form parallel seams atopposite sidesof a sheet,.said clutch operating `means comprising apull-rod as a part oiy each clutch operating mechanism, a leverconnected. with each pull-rod, oppositely arranged fulcrums l, for .saidlevers, an equalizing bar bearing on eachV oi' said levers, a movablesupport having a pivotal connection to the middle portionoi saidequalizing bar, and means for moving said. maw able part equalizing bar.levers and. pull-rods to simultaneously connect the motors thrdlish saidclutches to each oi.' said sealing bar reciprocating means.

7. A thermal sealing machine according 'to claim 5, wherein each sealingunit further comprises a work-support running parallel with the backingmember, said work-support being mounted on its unit, and adjustable withits unit on said ways toward and from the corre-A spondirig work-supportonthe opposite unit.

8. A thermal sealing machine according to claim 5, wherein each sealingunit further comprises a work-support running parallel with the backingmember, said work-support being.'

prises a work-support running parallel with thel t backing member, saidwork-support being mounted on its una, and adiumme with its unit on saidways toward and iromthe corre-l sponding work support on the oppositeunit,

and a guide rail mounted on said work-support, j

parallel to said backing member.

10. A` thermal sealing machine according to claim 5. wherein eachsealing unit further comprises a work-support running parallel with thebacking member, said work-support being mounted on its unit, andadiustable with its unit on said ways toward and from the corresponding.work-support on the opposite unit, means for adjusting saidwork-support laterally with relation to the backing member of its unit,

e a guide rail mounted on said work-support parallel to said backingmember, and means for adjusting said guide rail on said work-supportlaterally of said backing member.

f HARRY' 111. WATERS.-

